Grille louver tuyere: Grille louver tuyere is a new type of tuyere designed on the basis of fixed return louver. This type of tuyere can be divided into open type and fixed type. The outer frame and inner core are connected by door hinges and fixed type without inner core. Open and easy to install, can switch arbitrarily, clean or replace the filter, fixed price advantage is obvious. Open tuyere can also be used as overhaul tuyere. Usually the tuyere is equipped with filter screen. On the basis of fixed return louver, a novel return air outlet is designed. This type of return air outlet can be divided into two forms: open and fixed. The outer frame and inner core are connected by door hinges and fixed without inner core. Open and easy to install, can switch arbitrarily, clean or replace the filter, fixed price advantage is obvious. Open tuyere can also be used as overhaul tuyere. Usually the tuyere is equipped with filter screen.